Calculating machine



J y 1949- R. G. FOWLER ET AL 2,476,853

CALCULAT ING MACHINE Filed May 4, 1946 FIG.3

SHILLINGS INVENTORS ROLAND G.FOWLER OSCARE LARSEN AND I NELSON R.FR|EBERG THEIR Gttorneg Patented July 19, 1949 UNITED STATES PATENT OFFICE CALCULATING MACHINE poration of Maryland Application May 4, 1946, Serial No. 67,324

This invention relates to a calculating machine and more particularly to improved means for converting a machine of this type from the United States or decimal system of currency to the British or duodecimal system.

It has been customary in the past, when converting a calculating machine from the decimal system of currency to the British system, involving pounds, shillings, and pence, to replace the extreme right-hand keybank of the decimal machine with a modified keybank for handling pence, the pence bank consisting of a row of eleven keys instead of the customary nine. In the past, this change was usually effected by replacing the nine-key keybank with a row of eleven keys. This resulted in either a longer and more unwieldy bank of keys, if the spacing between keys was kept the same as in the decimal banks, or else a crowding together of the keys if the eleven keys were located within the space usually provided for nine. Neither of these expedients being entirely satisfactory or desirable, the present arrangement of pence keys was devised with a view to obviating the difliculty formerly encountered in converting decimal machines to the British currency system.

The invention comprises, in a calculating or similar accounting machine for the registration of items on a decimal base, having a differential mechanism including an actuator adapted to be positioned by means of abutments thereon cooperating with the stems of individually depressible keys of an associated bank, the provision of one or more auxiliary depressible keys for registering items on a base other than ten, located adjacent a bank of decimal keys, each of said auxiliary keys being adapted to cooperate with the abutments on the actuator so that the latter can be positioned to an extent commensurate with the value of a depressed decimal or auxiliary key.

According to the embodiment of the invention shown herein, a machine designed for decimal systems of currency may be converted to British currency by utilizing a conventional bank of nine amount keys to accommodate the numbers of pence from 1 to 9 The two additional keys which will be required for the pence (viz., the and 11 pence keys) are placed to the right of the 8 and 9 pence keys, respectively, and I thus do not create an undesirably long row of keys in the pence bank or result in a very close spacing of the keys, which makes them awkward to operate.

The 10 and 11 keys are provided with on!- 6 Claims. (Cl. 235145) set key stems, which are located between the keys in the 1 to 9 pence row, and the lower ends of the offset key stems cooperate with the same differential stop bar as the key stems of the keys 1 to 9, so as to provide for eleven steps of movement of the bar. The pence totalizer wheel and the pence type bar are thus controlled through eleven steps of movement to accumulate and record the items set up on the pence keys. The differential stop bar for the pence order is substantially the same as the stop bars for the decimal orders except for the fact that the abutments thereon which cooperate with the 1 to 9 keys are so spaced as to cause smaller increments of movement of the bar between adjacent keys. Also, an auxiliary stop member having two abutments thereon is secured to one side of the stop bar and spaced slightly therefrom. The abutments on the auxiliary member are adapted to cooperate with the lower ends of the offset key stems for the 10 and 11 keys so as to stop the differential stop bar in its 10 and 11 positions and thereby control the positioning of the totalizer wheel and the type bar for the pence order. The offset key stems for the 10 and 11 pence keys are in substantial alinement with the key stems of the 1 to "9 pence keys and are of a similar shape, so that they may cooperate with the same latching, locking, and zero stop bars as the l to 9 keys.

Accordingly, it is an object of the present invention to provide improved means for converting a calculating machine from one system of currency to another.

Another object of the invention is to provide means for converting one order of the calculating machine to an order containing a greater number of keys wherein the additional key tips are placed to one side of the row of keys composing the order to be converted, and are provided with offset key stems lying between the stems of the keys in said row.

A further object of the invention is to provide, in a calculating machine of the type having a bank of depressible keys and a differential stop bar adapted to cooperate directly with the stem of any depressed key, a series of depressible keys having offset key stems lying between the stems of the keys in the bank and cooperating with the differential stop bar in substantially the same manner as the regular keys.

Still a further object of the invention is to provide, in a calculating machine of the type having a bank of depressible keys, a differential stop bar adapted to cooperate directly with the stem of any depressed key, and a zero stop bar controlled by camming surfaces on the stems of the keys for preventing movement of the differential stop bar except when a key is depressed, e series o s ress ble k havi g efise y stems lying between the stems of the keys in the bank and cooperating with the differential stop bar and the zero stop bar in substantially the same manner as the regular key stems.

An additional object of the invention is to provide, in connection with a difierentiai mechanism of the character stated, a separate stop member having a series of abutments thereon, which is secured to one side 9f the differential stop bar for cooperation with the offset key stems of the additional key.

Other objects will become apparent from a reading of the following description of a par-.- ticular embodiment of the invention as applied 9 a e lhh wh ma e ef .ealeul ih mach ne.

1.1. the d wi s F ur 1 is a esssee enm levat n o a p r he ef a Al eal we e eddies ma h e which has been modified accordance with the present invention.

Figure 2 is a'perspectiveview of the 8, 9," l0, and11 pence keys and o f a fragmentary portion of their associated differential stop bar. Figure 3 is a plan view of the upper righthand corner of the keyboard.

Figure 4 is a fragmentary cross-sectional view taken along line 4-1-4 of Figure 1.

Figure 5 is a facsimile of a portion of a record tape made on a machine such as the one shown in Figures 1 to 4 inclusive,

' In connection with the following description, reference is made to United States Patent No. 1,386,021, issued to Heber C. Peters on August 2, 1921, for a showing of the basic machine. United State t n o- 8548? 5. s u d t Ne n White on April 19, 15232, may be referred to for a compiste eise su e ef th hh eeti m c sm partially shown herein, and United States Patent Ne. 2,062,731, issued to Charles Schroderon December 1, 1936, may be referred to for a detailed isclosu e of he e b a d mec an s Framework As Show in i u e 1 oi he dr w n s. the aj r ty he Work ng st c u t e m h he is u er eel tween wo s d me t e -hand fram ha in bee removed in e= ure 1 for a better view of the mechanism, and th ft-ha d me b n d igna d by e e erence numeral I 0. dournaled within the side frames and extending therebetween, is a main sh h I 2. which n h ase o e hande d eeh he s eh as ha h n n. the ters pa h her h h r f rred to suppo t h main operating handie for giving the machine cycles. of operation. Also journaled within the side rame d t il lng @1 he ma ne a diverging lever supporting shaft [4, while to the ear f he mac ne is eeated a, o-ea1 e e.r shait It, also journaled within the side frames. 'Phe 6 s epere iv l eehheeted w th e eih sheit so a e, h reeh d. h e s n er hea h e he m n. s aft i likewi re es by mea f heeh re hs'han le. m

Keyboard The keyboard in the present machine is sir n ilar. to the keyboards shown irrthe Peters ar d Schroder patents above referredto. As shown in the drawings, and particularly in Figure 1,

. slidably supported by means of slots formed in the top and bottom plates.

As shown in Figures 1 and 2, each of the 1 to 9 keys in each row of keys consists of a key stem 23, to the upper end of which is secured a key cap 21, which bears on its upper surface an appropriate numeral character. The upper end of each key stem is provided with an elongated slot 28 for receiving a, retaining bar 29 (Figures 1 and 4), located directl beneath the top plate 22 of the keyboard. The retaining bar is secured at each end in the end plates 24 and serves to retain the keys in place after they have been assembled Within the keyboard frame structute. The lower end of each of the key stems 26 is forked to form two legs 30 and 3|. As shown in Figure 1, a restoring spring 32 is coiled around the leg 3|, each of the springs being compressed between the bottom plate 23 and a shoulder 33 formed on the upper end of the leg 3|. The springs 32 serve to niaintain each of the keys in its raised position, with the lower end of the slot 23 in engagement with the lower surface of the bar 29. When a key is depressed, the lower end of the leg 30 strikes against the bottom plate 23 and limits the downward travel of the key, the lower end of the leg 3] projecting below the plate 23 so as toprovide a stop for the differential stop bar.

Located just beneath the top plate 22 and extending between the end plates 24 is a series of rods 34, there being one such rod located be,- tween each row of keys. The rods 34 are retained in place by means of a retaining strip 35 (see Figure 1), which is secured to the outer face of the forward end plate 24 and is provided with a series of spaced notches which engage in annular grooves 36 formed on the forward end of each of the rods 34. On each of the rods 34 are myotally mounted a latching bail 3'! (Figure 4) and a zero stop bail 38, these bails being pivoted thereon at their forward and rearward ends, as shown in Figure l The latching and zero stop bails on each of the rods 34 are pressed against .1. 1 key stems by means of a torsion spring 39, wrapped around the rod 34 and having its free I ehd 'eneae n w t the ba 31 n has een nr ieusl depr ss d in at row will.

he e ea e hen the latch ng b i 1 i a e gutwardly. due to, movement of the bail 3'1 out Q t ehetch 4. 1 o he pr iou depressed y- Qh he r ght-hand d of. e h y s m is h iey led. a ahim n urface 4 whi h operat i h. th h re e ba l. 3 H nee, Wh never a key is depressed, the Zero stop bail for that ha k w l e camped. eh wardly by the cammin surface 42 and retained in this position by the, ey tehia losses the hey i h ld in its de ressed position by the latching bail 31. The zero stop bail 38 is provided at its forward end with a zero stop arm 43 (Fig. 1), which is held in the path of a differential stop bar 44 by the torsion spring 39 when the keys of the row concerned are all in their raised positions. However, when a key is depressed, the zero stop bail 38 is swung outwardly by the camming surface 42 on the key stem, and the zero stop arm 43 is thus moved out of the path of the differential stop bar 44 to thereby allow the latter bar to move forward in itghe machine until it is stopped by a depressed In order to enable the entire keyboard to be cleared, there is provided at the front end thereof a key release bail 45, pivoted at 48 in a forwardlyextending portion of each of the side plates 25. The bail 45 is provided with rearwardly-extending fingers 41, which engage the inner faces of the bails 3'! and 38 and cause the bails to be cammed outwardly when the bail 45 is rocked clockwise, as viewed in Figure 1.

As mentioned above, the lower end of each key stem 26 is forked so as to form two legs, 38 and El. The shorter of these two legs, 3!], is provided with an car 48, which is adapted to cooperate with a locking rail 49 (Figure 4) which is rockably mounted in the bottom plate 23 of the keyboard by means of tenons on the rail 49, which engage in apertures formed in the bottom plate 23. There is one such rail for each bank of keys, all of the rails being connected together by means of a cross bar 50 extending laterally across the keyboard. This cross bar is yieldingly urged toward the right-hand side of the machine, thereby biasing all of the locking rails 49 toward their associated key stems. Means (such as that shown in the patent to Schroder) is provided, however, for holding the cross bar 50 to the left, so as to maintain all of the locking rails 49 in their disengaged positions, as shown in Figure 4, until after the operation of the machine has commenced, after which the cross bar is released to bring each of the locking rails 49 up against its related key stems. The flanged upper edge of the locking rail will thus be brought either above or below the ear 48 formed on each of the legs 35 to thereby lock the keys in either their depressed or undepressed positions during operation of the machine.

The keyboard assembly is retained in position in the machine by means of notches, formed in the rear edges of the side plates 25, which engage with a shaft 51 extending between the side frames of the machine, and also by forked extensions, located at the forward ends of the side plates 25, which engage over a rod 52 located toward the front of the machine and supported between the side frames. The keyboard assembly is retained against displacement from its position on shaft 5! and rod 52 by means of latches mounted on the rod 52 and engaging with studs located in the side plates 25 of the keyboard. These retaining latches have not been shown in the present drawings but may be found in the Peters patent referred to above. Located beneath the rod 52 and secured thereto is a plate 53, which serves to maintain proper spacing between the side frames of the machine and also to aid in supporting the rod 52.

Dz'fi'crentz'al mechanism The differential stop bars for the decimal orders of the machine are similar to the differential stop bar 44 for the pence order and, like this bar, are supported at their forward ends on the rod 52 and at their rear ends are pivotally connected at 54 to a series of diverging levers 55', which are loosely mounted for rotation upon the shaft [4. The stop bars are prevented against lateral displacement at their forward ends by means of a comb plate 56, which is supported between the side frames and provided with a series of vertical slots within which the stop bars are slidably received. Each of the stop bars is urged in a forward direction by means of a long tension spring 51 secured at its rearward end to a stud 58 mounted on the differential stop bar and at its forward end to the comb plate 56. The stop bars are held in their rearward positions against the urgency of the springs 5'! by means of a restoring bail 59 extending across the machine in front of all of the diverging levers and supported at each end on an arm 60 pinned to the shaft I4. Means is provided for rocking the arms 60 counter-clockwise each time the operatin handle is pulled forwardly, so as to permit the diverging levers and the differential stop bars to move forwardly under the urgency of the springs 5! until the bars are stopped by reason of abutments thereon striking against the lower ends of the keys 3! of the depressed keys. These abutments, in the case of the stop bars in the decimal orders, are similar to abutments 6| provided on the bar 44 but are spaced slightly farther apart so as to provide nine steps of movement instead of eleven. When the operating handle is returned to its normal position, the restoring bail 59 is likewise returned to the position shown in Figure 1 to thereby cause the diiferential stop bars and the diverging levers to be returned to their normal or unmoved positions.

Secured on one side of each of the stop bars is an adjustment bar 62, which is provided at its forward end with an abutment 63, supported at the end of a gooseneck 64. On the rear end of each adjustment bar 62 is mounted a stud 65 on the end of a gooseneck 55. The gooscnecks 65 and 66 are utilized for the purpose of facilitating the adjustment of the abutment 53 and the studs 65 after the machine has been assembled.

The abutments 63 are adapted to cooperate with the comb plate 56 to limit the forward travel of the stop bars 44 to nine steps of movement in the case of the decimal banks containing nine amount keys and to eleven steps of movement in the case of the pence bank shown in Figure l. The studs 65 are adapted to cooperate with fingers 61 formed on a series of complementary arms similar to an arm 68 for the pence bank, each of which arms is secured to the left-hand end of one of a series of sleeves 69, freely rotatable upon a shaft 10 extending across the machine between the side plates. The complementary arms form a part of the subtraction mechanism of the Allen- Wales type of machine, this mechanism being completely described in the patent to White referred to in the early part of this description.

The purpose of the complementary arms is to enable the totalizer actuator racks to be set to th complement of the number set up on the keyboard while the type bars are positioned under the control of the diverging levers to print the amount represented by the keys depressed on the keyboard. Accordingly, in the decimal or nine key orders of the machine, the arms are arranged so that the fingers 6! are nine steps ahead of the studs 65 when the differential stop bars are resting against their zero stop arms 43, while, in the case of the pence order, the finger H on the arm 68 is located twelve steps ahead of its stud 65 these two members. racks will now be-co'ntrolled by the complemenwhen the differential stop-bar 44 is in its zero position.

Secured to the right-hand end of each of the sleeves 69 is an arm 12 carrying a stud 13 at its rearward end. For normal adding operations, this stud is received within a pair of elongated slots 14 provided in the forward end of each of the similar arms 75 and 16. The arm 15 is integral with'its associated diverging lever '55, while the arm 16 is integral with an upwardly-extending actuator rack arm 11, which supports at its upper end a totaliZer-actuating rack 18 and a stop plate 19. The stop plate 19 is secured to the totalizer actuating rack 18 by means of rivets or otherwise,

' and the plate "and the rack are urged in a rearward direction, as viewed in Figure 1, by means of a carrying spring 88, the rack 18 being supported for forward and rearward sliding movement on the upper end of the arm H by means of a pair of studs M on the rack 73, which are received in a pair of elongated slots provided in the upper end of the arm 11.

Totalizer Cooperatin with the rack teeth on each of the racks 18 is a series of totalizer pinions similar to the pinion 32 for the pe'nce order but having ten teeth insteadof twelve. The totalizer pinions are mounted on a shaft 33 carried by a pair of arms 84 pivotally mounted at their forward ends on the shaft 51. Secured to each of the totalizer pinions is a totalizer wheel provided with a flanged rim on the outer periphery of which are inscribed appropriate numeral characters. These characters may be observed through a sight opening provided in the calculating machine casing, so as to enable the machine operator to read ed the total contained on the totalizer wheels. The totalizer wheels for the decimal orders bear numerals from to 9, while the pence wheel 86 bears numerals from 0 to 11. 'The totalizer wheels are prevented against displacement, when rocked out of engagement with the rack 18, by means of a series of aliner plates 8? rigidly secured upon rods 88 and 39, which are supported within the side frames. On the forward end of each of the aliner plates 81 is formed a tooth '83, which is adapted to engage between adjacent teeth on the totalizer pinions when the totaliz'e'r is rocked out of engagement with the rack 78. A

more detailed description of the totalizer mechanism may be had by referring to the Peters and White patents hereinbefore referred to.

Each of the complementary arm-s is connected with its associated diverging lever 55 by means of a tension spring 9f, which urges the arm in a clockwise direction. For subtract operations, the complementary arms, the sleeves 69, and the arms i2 are shifted toward the reader in'Figure 1, so as to move-the 'fingers '61 and H into the plane of the studs65 and at the same time move the studs 13 out of engagement with the elongated slots 74 in the arms to therebyjuncouple the totaliz'er actuator rack'arms 11 from the diverging IGVEIS a'h'd enable ili'dep'hdeht movement of The 'tota'lizer actuating t'ar'y arms rather than by the differential stop bars, so as to cause a complementary amount to 'be 'e'nteredinte the totalizer wheels.

For adding operations, "the complementary arms, the sleeves69; and the arms 72 are shifted to the left or away fromth-e reader in Figure 1, so as. to ca'rryth-e-fingers 61 and il out of the plane of'tlre studs'fifi and to move the studs '13 into the elongated slots 14 formed in the arms 15 to thereby render the complementary mechanism ineffective and to directly couple the totalizer actuator rack arms H with the diverging levers 55.

Printing mechanism Integral with each of the divergihg levers '55 is a rearwardly-extending armd92, whi'eh is pit!- bted at 93 to the upper arm of a U-shaped link B l, which link is pivoted at its lower 'end on a stud secured to the type bar 95. A shrihg' clip iii, secured to the type bar at, tends to retain the link '94 on the stud 95. The upper end of the type bar is provided with ten number type '98 in the case of decimal orders of the machine 'ahd with twelve such number type in the case of the pence order showh in Figure 1. The 93 are slide ably meumed ih horizontal slots formed in the upper end of the type bar 'Qi? and are retained therein by means of a retaining plate 99. The type bar 96 is supported for vertical sliding move ment by means of guide plates I00 and NH, located to the front and the rear, respectively, of the bars A comb plate R32 is secured to the rear guide plate iii! and is provided with a series of slots for slidably receiving the bars 96, there by preventing their displacement in a lateral direction.

The type 98 are adapted to be driven by a ham iner 683 against an ink ribbon (not shown) loc'ated in front of record material 124 supported on a platen see, which is rotatably mounted on a shaft 566. The record material is unwound from a supply roll and led around a guide plate "107 and thence around the platen 1B5. Theha'r'nmer's use are rotatably mounted on a shaft H18, support' ed at each end by a pair of printing mechanism side plates (not shown). Each of the hammers is urged toward the type 98 by a spring 39, connected at one end to a tail formed on the hammer and at the other end to a bent-over flange on a comb till, which serves to guide the hammers in their travel toward and from the type 98. Each of the hammers is retained in the position shown in Figure l by means of a hook H! formed on the hammer, which engages with a latch H2 pivotally mounted 'on a-shaft i is and urged counterclockwise into engagement with the hook i H by a spring H4.

On each of the type bars is located a stud H5, which cooperates with the rearward endof a tripping finger i H3 rotatably mounted on a rod iii supported between a pair of'arms il whio'h are loose on the shaft E3. The tripping fingers are urged in a counter-clockwise direction about the rod ill by means of springs H9, while the arms H8 are urged in a similar direction by means of springs [20. Secured to the shaft I08 is a pair of arms H29, which support between them a restoring bail I22, which serves to restore all of the hammers N33 to the position shown in Figure 1 after they have been firecl'against the type 98 during a printin operation. The arms I2! are moved first clockwise-and then counterclockwise during a machine cycle by means of connections from the rear shaft it, which connections are not shown herein but are completely shown and described in the above-mentioned patent to Peters.

Secured to the rear shaft N5 is a pair of arms 523 (only -one of which'is shown) each bearing a stud I24, which is adapted to engage with a shoulder I25 formed on each of the arms 8. When the operating handle of the'machine is operated, the shaft i6 is rocked first counterclockwise and then clockwise in a manner not shown herein but fully shown and described in the patent to Peters, so as to cause the studs I24 to engage the shoulders I25 on the arms I58, thereby rocking the arms in a clockwise direction about the shaft I08. In this manner, any of the fingers I I6 which have been released for counter-clockwise movement by their springs II9 by the upward movement of the type bars 96 will be brought into engagement with notches formed in the latches I I2 and, when the rod II! is moved forwardly in the machine, will cause the latches to release the hooks III formed on the hammers I03 and allow the hammers to be driven against the type 98 by their springs I89.

Pence OTCZGT As previously stated herein, it is the purpose of the present invention to convert the units of cents order of a United States currency type of machine into a pence order in a simple and inexpensive manner. As shown in the drawings, this is accomplished by adding a 10 key and an 11 key to the row of keys for the units of cents order. These two keys are located to the right of the 8 and 9 keys for this order, but each-- is provided with an ofl'set ke stem I26 (Figures 2 and 4) which lies in substantial alignment with the key stems 26 for the l to 9 keys. Each of the key stems I26 is provided with an elongated slot I28 for receiving the key retaining than the legs 3| on the key stem 26 (see Figure 4). A key restoring spring I32 (Figure l) is coiled about the leg I3I and is compressed between the bottom keyboard plate 23 and a shoulder I33 formed on the side of the leg I3I. The left-hand edge of the key stem I26 is provided with two notches I40 and HI, which are similar in every respect to the notches 40 and 4! formed in the key stems 26. These two notches cooperate with the latching ball 31 for the 1 to 9 keys of the pence order, so as to integrate the 10 and 11 pence keys into the key latching mechanism for this bank. 0n the right-hand edge of the key stern I26 is provided a camming surface I42, which is adapted to cooperate with the zero stop bail 38 for the 1 to 9 pence keys in exactly the same manner as the camming surfaces 42 on the convent onal ke stems. Similarly, an ear I48 is provided on the short leg i1 6 for cooperat on with the lock ng ra l 49 in exactly the same manner as the ears 48 on the conventional key stems. When one of the key stems I26 is de ressed. the lower end of the leg I3I is proect d n o the path of one of t e abutment I34 formed on an auxiliary stop member I35, the key stem for the 10 key cooperating with the forward abutment I34 and the key stem for the 11 key cooperating with the rearward abutment 134. This member I is secured to the right-hand side of the pence order differential stop bar 44 and is spaced a short distance therefrom by means of spacing collars I36. The pence order differential stop bar 44 is similar to the conventional differential stop bars except that the abutments 6I formed thereon are spaced somewhat more closely together than usual, so as to enable the bar 44 to partake of eleven steps of movement in the space usually provided for nine. The eleven pence keys thus control the differential stop bar through eleven steps of movement by means of the lower ends of the key stems 26 and I26 in cooperation with the abutments BI and I34. The pence pinion 82 is provided with twelve teeth instead of the customary ten, and the pence type bar 96 carries twelve type 98 instead of the usual ten. Hence any number of pence from 1 to 11 may be accumulated on the totalizer wheel 86 and printed by the type bar 96 on the record material I04.

Each of the key stems I26 is provided at its upper end with a bent-over extension I31, which is secured at its other end with an abbreviated key stem I39, which is provided with a key cap I21. The lower end of the abbreviated key stem I38 is provided with a reduced portion I39, which is received in a slot provided therefor in the top plate 22 of the keyboard for guiding the key stem I 38 in its up-and-down movement.

In Figure 5, a sample portion of a record tape I43 illustrates the manner in which the numbers entered on the keyboard of the machine are printed on the record material by the type 98. In the example shown in Figure 5, four numbers, involving pounds, shillings, and pence, have been added together and a total has been taken to yield the sum of the four numbers involved. It will be observed that the number characters for the pence items are somewhat smaller than the rest of the numerals, this being due to the fact that there are twelve pence type 98 located within the space on the type bar 96 usually provided for ten. Hence the type 98 for the pence type bar must be somewhat smaller than normal, with the result that somewhat smaller printin of pence items will result. Totals are taken on the present machine in exactly the same manner as on the machine disclosed in the aforementioned Peters patent and hence will not be described herein.

It will be observed from the foregoing description that a United States currency type of calculating machine may be simply and easily converted into a machine for handling British currency transactions in accordance with the teachings of the present invention. The only change required in the keyboard is the provision of four additional slots, two for receiving the key stems I 26 and two for receiving the abbreviated key stems I38. In the differential operating mechanism, the only required change is in the spacing of the abutments 6I on the differential type bar 44 and in the provision of the auxiliary stop member I35 on the side of the bar 44.

It is also necessary, of course, that the totalizer pinions be modified by the provision of additional teeth and that the type bar 98 carry twelve type 98 instead of the customary ten. These changes, however, are all easily made, and hence the standard United States currency machine may be converted into a machine for handling British currency at very little cost.

What is claimed is:

1. In a machine of the class described having a keybank provided with a series of depressible keys each having a key stem a portion of which serves as a stop element when the key is depressed, and a stop bar associated with said keybank and having a series of abutments thereon for coacting differentially with said stop elements so as to control said bar through a plurality of steps of movement, the combination of an auxiliary key bank located adjacent to said firstnamed keybank and comprising one or more depressible keys having oflset key stems, said offset stems being located between the stems of the keys in the adjacent first-named keybank and each having a portion which serves as a stop 1' element when the key is depressed; and addi- .tional abutments provided on said stop bar for coacting with the stop elements of said offset key stems to thereby control said bar through additional steps of movement.

2. The invention as defined in claim 1 wherein said additional abutments are formed on a separate member which is securely attached to said which serves as a stop elementwhen the key is depressed, a stopbar associated with said key bank having a series of abutments thereon for coacting differentially with said stop elements,

to stop said bar in any one of a plurality of positions, a zero stop member cooperating with said differential stop bar to prevent movement of the bar when no keys in said keybank are depressed,

and camming surfaces on said key stems for mov ing said zero stop bar to ineffective position when any of said keys are depressed, the combination of an auxiliary keybank located adjacent to said first keybank and comprising one or more depressible keys having ofiset key stems, said ofiset stems being interposed'between the stems of the keys in the said first keybank and each having a portion which serves as a stop element when the key is depressed, camming surfaces on said ofi'set key stems similar to the camming surfaces on the stems of the keys of said first keybank and located in alignment therewith, the camming surfaces on said offset key stems cooperating with said zero stop member to move the Zero stop member to inefi'ective position when any of the keys in said auxiliary key bank are depressed, and additional abutments provided on said stop bar for coacting differentially with the stop elements of said offset key stems to thereby stop said bar in as many positions in addition to said plurality of positions as there are keys in said auxiliary keybank.

5. The invention as defined in claim 4 wherein said additional abutments are formed on a separate member which is securely attached to said differential stop bar.

6. The invention as defined in claim 4 wherein said additional abutments are formed on a separate bar which is secured to one side of said differential stop bar and in spaced relationship thereto.

ROLAND G. FOWLER. OSCAR F. LARSEN. NELSON R. FRIEBERG.

REFERENCES CITED The following refereircesare of record in the file of this patent:

UNITED STATES PATENTS Great Britain 1927 

